For those who are looking to control the aircraft from external tablet devices, I have now released support in my Android XPlaneCDU app to support the SSG 747-8. So you can control the CDU directly from any Android tablet/phone, and quickly enter in data without having to use the mouse. It is a native Android app, so runs very quickly and completely full screen, and works on really old devices so you can get them quite cheaply.
Also, I have updated XTextureExtractor so that it also supports the SSG 747-8. This plugin can extract the textures for the ND, HSI, EICAS, and CONFIG screens, and display them in separate movable windows on any of your monitors, exported to an Android device, or exported to a remote PC with a Java client.
These plugins and apps are all open source and completely free. Check them out at:
https://forums.x-plane.org/index.php?/files/file/42643-xplanecdu-for-android/
https://forums.x-plane.org/index.php?/files/file/42612-xtextureextractor/